edu.washington.cs.knowitall.regex

Class Match<E>

java.lang.Object

edu.washington.cs.knowitall.regex.Match<E>

Type Parameters:

E -

Direct Known Subclasses:

Match.FinalMatch, Match.IntermediateMatch

public abstract class Match<E>
extends Object

A class to represent a match. Each part of the regular expression is matched to a sequence of tokens. A match also stores information about the range of tokens matched and the matching groups in the match.

Author:

Michael Schmitz

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	Match.FinalMatch<E> A match representation that has efficient method calls but is immutable.
static class	Match.Group<E> A captured group in a matched expression.
protected static class	Match.IntermediateMatch<E> A match representation that is mutable but many method calls compute values instead of returning stored values.

Field Summary

Fields

Modifier and Type	Field and Description
protected List<Match.Group<E>>	pairs

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	Match()
protected	Match(Match<E> match)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	add(Expression<E> expr, E token, int pos) Convenience method for add(new Group(expr, token, pos)).
boolean	add(Match.Group<E> pair)
boolean	addAll(Collection<Match.Group<E>> pairs)
abstract int	endIndex()
Match.Group<E>	group(String name) Retrieve a group by name.
abstract List<Match.Group<E>>	groups()
boolean	isEmpty() True iff this match contains no pairs.
int	length()
List<Match.Group<E>>	pairs() Pairs differ from the matching groups in that each regular expression element has a pair to associate the element with the text matched.
abstract int	startIndex()
abstract List<E>	tokens()
String	toMultilineString()
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

pairs

protected List<Match.Group<E>> pairs

Constructor Detail

Match

protected Match()

Match

protected Match(Match<E> match)

Method Detail

add

public boolean add(Match.Group<E> pair)

addAll

public boolean addAll(Collection<Match.Group<E>> pairs)

add

public boolean add(Expression<E> expr,
          E token,
          int pos)

Convenience method for add(new Group(expr, token, pos)).

Parameters:

expr -

token -

pos -

Returns:

isEmpty

public boolean isEmpty()

True iff this match contains no pairs. This should only happen on an IntermediateMatch that has not had any pairs added to it yet.

toString

public String toString()

Overrides:

toString in class Object

toMultilineString

public String toMultilineString()

startIndex

public abstract int startIndex()

Returns:

the index of the first token matched (inclusive start).

endIndex

public abstract int endIndex()

Returns:

the index one past of the last token matched (exclusive end).

pairs

public List<Match.Group<E>> pairs()

Pairs differ from the matching groups in that each regular expression element has a pair to associate the element with the text matched. For example, 'a*' might be associated with 'a a a a'.

Returns:

all pairs in this match.

groups

public abstract List<Match.Group<E>> groups()

Returns:

all matching groups (named and unnamed).

tokens

public abstract List<E> tokens()

Returns:

all matched tokens.

length

public int length()

Returns:

the number of tokens in the match.

group

public Match.Group<E> group(String name)

Retrieve a group by name.

Parameters:

name - the name of the group to retrieve.

Returns:

the associated group.